Officials at the Centers for Disease Control and Prevention announced Tuesday that despite continued efforts to halt the multistate outbreak of an intensely noxious, mayonnaise-borne virus, they have been unable to combat its deadly progress.

The first known case of the viral strain, which thrives in the delicious, creamy environment of mixed egg yolks, vegetable oil, and vinegar, was recorded by the CDC just three weeks ago and may be the strongest and most infectious contagion ever detected in mayonnaise or a mayonnaise-related substance. The agency's leading scientists have determined the epicenter of the growing pandemic to be an infected roast beef sandwich in the St. Charles suburb of Chicago.